Machbeth,William Shakespeare

I studied Macbeth last week at school. It's one of the most famous tragedies of William Shakespeare. Macbeth is the Baron* of Glamis and at the beginning of the story he's an a hero, a strong general but, after the prophecy of the three witches an uncontrollable ambition invades Macbeth and his wife, Lady* Macbeth. She is the most wicked character of the tragedy for three reasons:
1) She commands her husband like he's a puppet
2) She is the one who planned the murder of the King* of Scotland, Duncan
3) After the murder, she never repented for of her actions even if the vision of blood on her hands led her to suicide
The sense of guilt, the darkness, the blood, the sleep of innocence that disappears after the murder, and the ambition are the most important themes of this tragedy.

* - In this context, these are titles and as such should be capitalized in modern English. As a side note, I believe that Macbeth's title is actually 'Thane', but I'm not a Shakespearean scholar.